It might be a natural feature formation, or possibly a sunken, round man-made object. UFO Battles Captured on Video?

这种形状可能是由一种自然特征所形成，或者也可能是一个沉没在海底的圆形人造物体。

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Racking up another Soviet first, this mission became the first man-made object to successfully orbit another celestial body.

这艘探测器又前让苏联创造了一个第一：它成为首个成功围绕另外一个天体运行的人造物体。

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The white of the villa allows it to stick out as a man-made object on the landscape during the changing colours of the season.

随着季节的变换，颜色也在变换，使得别墅的白色部分作为人造物体突出出来是被允许的。

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It measures 5, 500 miles and is the only man-made object observable from the moon.

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On November 17, 1998, Voyager 1 became the most distant man-made object from the Sun when it reached a point further away than NASA probe Pioneer 10, which launched in 1972.

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